Methionine is one of the most important essential amino acids in human and animal nutrition. It is the most limiting amino acid in poultry and the largest additive in feed. Demand for methionine has been increasing more rapidly compared to other aspartate-family amino acids (i.e., lysine and threonine) due to the rising consumption of meats in developing countries. The major producers are adding capacity to meet the increasing demand.
Methionine is currently produced by chemical methods that involve highly toxic petrochemical raw materials such as hydrogen cyanide (produced from natural gas and ammonia), acrolein (produced from propylene) and methyl mercaptan (produced from methanol and sulfur). Raw materials used in the chemical-based method require extensive environmental and safety considerations in the operations, and produce a significant amount of waste stream.